A Survey of BitTorrent Performance

Since its inception, BitTorrent has proved to be the most popular approach for sharing large files using the peer-to-peer paradigm. BitTorrent introduced several innovative mechanisms such as tit-for-tat (TFT) and rarest first to enable efficient distribution of files among the participating peers. Several studies examining the performance of BitTorrent and its mechanisms have been published in the literature. In this paper, we present a survey of performance studies of BitTorrent from 2003 to 2008. We categorize these studies based on the techniques used, the mechanisms studied and the resulting observations about BitTorrent performance. Many of the performance studies also suggested modifications to BitTorrent's mechanisms to further improve its performance. We also present a survey of the suggested improvements and categorize them into different groups.